I am writing the query to show the data entries for a specific year. Date is stored in dd/mm/yyyy hh:mm:ss.(Date TIMESTAMP - e.g. 12/2/2014 0:00:00).
I am trying to display the two columns(name, orderdate) filtered by a specific year(year from orderdate). The requirement is to enter the specific year(2010 or 2020 etc) not the entire date. I tried using date_format() and regexp_replace() with WHERE but nothing helped.
Can someone help me?
If your are storing the date -- incorrectly -- as a string, then you can use string functions to do what you want:
where orderdate like '__/__/2010%'
However, you should really put your effort into storing the date using a correct format -- YYYY-MM-DD for strings at least.
Related
I need to store a date on MM/YYYY format (without the day) on PostgreSQL.
Is that possible?
I don't want to just pick a day and store the day as well because that would be an incorrect information.
thanks.
mm/yyyy is not a valid date. The day is part of it, and cannot be removed. One alternative would to store the data in a string datatype instead of date, but I would not recommend that: doing so exposes you to data integrity issues (something like 13/2010, for example, is not a valid date part).
For this reason, I would still recommend using the date datatype. You can just ignore the day when accessing the data, if that's not relevant for you. You can also create a computed column based on the date, that displays the information in the format you want:
create table mytabnle (
...
mydate date,
mystr text geneated always as (to_char(mydate, 'mm/yyyy')) stored
);
I need help in figuring out the date conversion logic in Snowflake. The documentation isn't clear enough on this.
In SQL Server, I would try
SELECT CONVERT(DATE, '20200730', 101)
and it gives me '07/30/2020'.
If I try the following in Snowflake,
to_varchar('20200730'::date, 'mm/dd/yyyy')
it gives me '08/22/1970'. Why would it give an entire different date? Need help in getting the logic with the correct date.
The issue with what you are doing is that you are assuming that Snowflake is converting your string of '20200730'::DATE to 2020-07-03. It's not. You need to specify your input format of a date. So, 2 options based on your question being a bit vague:
If you have a string in a table and you wish to transform that into a date and then present it back as a formatted string:
SELECT TO_VARCHAR(TO_DATE('20200730','YYYYMMDD'),'MM/DD/YYYY');
--07/30/2020
If the field in the table is already a date, then you just need to apply the TO_VARCHAR() piece directly against that field.
Unlike SQL Server, Snowflake stores date fields in the same format regardless of what you provide it. You need to use the TO_VARCHAR in order to format that date in a different way...or ALTER SESSION SET DATE_OUTPUT_FORMAT will also work.
Try select to_varchar(TO_DATE( '20200730', 'YYYYMMDD' ), 'MM/DD/YYYY'); which produces 2020-07-30
You may need to refer to https://docs.snowflake.com/en/user-guide/date-time-input-output.html#timestamp-formats
My question, now I have table customer in Postgresql and contain the column name is update (for keeping track of update customer info date.)
The date format is ex:20170302 but I want to convert to be 02/03/2017.
Note: the datatype of the update is character varying.
I have tried several times to find all the solutions by google but not fix.
First, you should fix the data type to be a proper date or datetime. Don't store dates as strings!
But you are. You can convert the value to a date and then back to a string:
select to_char(to_date(update, 'YYYYMMDD'), 'DD/MM/YYYY')
The documentation contains the formatting elements that you can use.
I am using MS SQLServer and trying to insert a month/year combination to a table like this:
INSERT INTO MyTable VALUES (1111, 'item_name', '9/1998')
apparently, the above command cannot work since
Conversion failed when converting date and/or time from character string.
Because 9/1998 is a bad format. I want to fix this and this column of the table will show something like:
9/1998
12/1998
(other records with month/year format)
...
Can someone help me with this?
thank you
SQL Server only supports full dates (day, month, and year) or datetimes, as you can see over on the MSDN data type list: http://msdn.microsoft.com/en-us/library/ff848733(v=sql.105).aspx
You can use a date value with a bogus day or store the value as a string, but there's no native type that just stores month/year pairs.
I see this is an old post but my recent tests confirm that storing Date or splitting the year and month to two columns (year smallint, month tinyint) results in the overall same size.
The difference will be visible when you actually need to parse the date to the filter you need (year/month).
Let me know what do you think of this solution! :)
Kind regards
You can just use "01" for the day:
INSERT INTO MyTable VALUES (1111, 'item_name', '19980901')
You can:
1) Change the column type to varchar
2) Take the supplied value and convert it to a proper format that sql server will accept before inserting, and format it back to 'M/YYYY' format when you pull the data: SELECT MONTH([myDate]) + '/' + YEAR([myDate]) ...
You may want to consider what use you will have for your data. At the moment, you're only concerned with capturing and displaying the data. However, going forward, you may need to perform date calculations on it (ie, compare the difference between two records). Because of this and also since you're about two-thirds of the way there, you might as well convert this field to a Date type. Your presentation layer can then be delegated with the task of displaying it appropriately as "MM/yyyy", a function which is available to just about any programming language or reporting platform you may be using.
if you want use date type, you should format value:
declare #a date
SELECT #a='2000-01-01'
select RIGHT( convert (varchar , #a, 103), 7) AS 'mm/yyyy'
if you want make query like SELECT * FROM...
you should use varchar instead date type.
Problem: I have a large database table (~500k records) which has a list of dates stored in a varchar2(15) column. These dates are stored in varying formats, ie. some are yyyy-mm-dd, some are mm/dd/yyyy, some are dd/mm/yy, some are mm/dd/yy, etc. Ie:
1994-01-13
01/13/1994
01/13/94
13/01/94
13/01/1994
etc
I need to be able to shift these dates slightly, for example to add 30 days to each date. (This is an oversimplification of my objective but it's easier to explain this way).
If all the dates were formatted consistently, I would achieve this as follows:
UPDATE history_table
SET some_date_col =
to_char(to_date(some_date_col, 'mm/dd/yyyy')+30, 'mm/dd/yyyy')
WHERE some_date_col IS NOT NULL;
Due to the size of the database, I cannot afford to loop through the values one by one and parse the date value. Can anyone suggest a means to accomplish this without loops, ie with a mass UPDATE statement?
Are the formats of these dates really that important? They should be datetime columns. Then you could just use date math functions on that field.
well, you've got a real problem here.
07/07/1994 is valid for 'MM/DD/YYYY' and 'DD/MM/YYYY'
However, outside of that issue, you can try nesting decodes.
I entered the following dates into a varchar field:
01/12/2009, 01-12-2009, 2009-01-12, 01/12/09
and using the below, I was consistently returned 1/12/2009. You'll have to figure out all the patterns possible and keep nesting decodes. The other thing you could do is create a function to handle this. Within the function, you can check with a little more detail as to the format of the date. It will also be easier to read. You can use the function in your update statement so that should be faster than looping through, as you mentioned.
(for what its worth, looping through 500k rows like this shouldn't take very long. I regularly have to update row by row tables of 12 million records)
select mydate,
decode(instr(mydate,'-'),5,to_date(mydate,'YYYY-MM-DD'),3,to_date(mydate,'MM-DD-YYYY'),
decode (length(mydate),8,to_date(mydate,'MM/DD/YY'),10,to_date(mydate,'MM/DD/YYYY')))
from mydates;
and here is the update statement:
update mydates set revdate = decode(instr(mydate,'-'),5,to_date(mydate,'YYYY-MM-DD'),3,to_date(mydate,'MM-DD-YYYY'),
decode (length(mydate),8,to_date(mydate,'MM/DD/YY'),10,to_date(mydate,'MM/DD/YYYY')))
IMHO, you have a bigger problem:
If some dates are dd/mm/yyyy and some are mm/dd/yyyy how can you difference which format applies for certain date?
for example, how can I know if a value "12/09/2008" means December or September?